Square+Root+Functions

Square Root Functions- **Alison** First thing you need to know is you **cannot** take the square root of a negative number as it will be an imaginary number. Also taking the square root of a variable gives you two answers. One answer is positive and the other answer is negative.

When dealing with square root equations you have to think of the problem as two separate equations, other wise it will not be an equation, due to the vertical line rule. The vertical line rule tells us that we **cannot** have a line graphed that a vertical line would go through twice. Therefore from knowing that the answer of a square root is both negative and positive, you have to treat the equation as two separate equations, One positive and one negative.

The negative part of the equation is: so the x- intercept is 4. The positive part of the equations is: so the x intercept is -4. To find the x-intercept of a line you solve the equation for y=0. See Greg’s post on intercepts for more info on finding x and y intercepts.

Once you know your x-intercept in this case you can then find your domian. The Domain is all the possible x vales. So your domain for is [4, ∞ ). and the domain for [[image:equation(5).png width="68" height="16"]] is [-4, ∞).

When you divide a square root, the slope of the line will flatten out towards the x-axis. The graph looks like half a parabola, turned 90 degrees



__**Regular problem:**__ **
 * [[image:equation.png]] get ride of the square root and simplify

**Solve for x intercept** **Set y to 0** **Find the number that will make the right side 0** x= -4
 * __EF-122:__**

**Solve for y intercept** **Set x to 0** y= +/-2 **Simplify and get ride of the square root**